Electronic pulse generator



May 19, 1953 N. A. MOERMAN ELECTRONIC PULSE GENERATOR 6 Sheets-Sheet 1 Filed June 30, 1950 IL i! x 05 on on 5 v mm mm mmoimuzwo 50. oEEim wmxim 3059B INVENTOR. NATHAN A. MOERMAN ATTORNEY May 19, 1953 6 Sheets-Sheet 2 Filed June 30, 1950 mm mm wmmzmo A bh .N .UE v 8 3 g mm mm 6 ow I 3 E on 3P 3 3 mm GP $1 oom+ W 2 mm E m i b m INVENTOR NATHAN A. MOERMAN ca b n1- w on CD y 1953 N. A. MOERMAN ELECTRONIC PULSE GENERATOR 6 SheetsSheet 3 Filed June 30, 1950 MOE Quinn 5530 INVENTOR. NATHAN A. MOERMAN BY E ATTORNEY May 19, 1953 N. A. MOERMAN ELECTRONIC PULSE GENERATOR Filed June 30, 1950 6 Sheets-Sheet 5 H 2 Q m g 2 M Q mmPEIW mw Il mWJDn.

INVENTOR. NATHAN A. MOERMAN Patented May 19, 1953 ELECTRONIC PULSE GENERATOR Nathan A. Moerman, Jackson Heights, N. Y., as-

signor to Potter Instrument Co. Inc., Great Neck, N. Y., a corporation of New York Application June 30, 1950, Serial No. 171,303

9 Claims.

The present invention relates to electronic pulse generators and, in particular, pulse generators suitable for use in electronic computers and the like.

Electronic computers are analogous to mechanical computers in carrying out the mathematical processes of addition subtraction, multiplication and division. Whereas the mechanical computer utilizes mechanical wheels, cogs, latches, etc., the electronic computer utilizes electrical pulse generators, electronic counters, pulse combining circuits, etc. One important portion of the electronic computer is a pulse generator which will generate any predetermined number of pulses from 1 through 9 and a carry pulse representing 10. The present invention concerns a simple and effective pulse generator for this purpose.

In the past computer pulse generators have required large numbers of vacuum tubes and complicated circuits. According to the present invention the generation of any given number of pulses utilizes only three vacuum tubes, a double triode phase shifting pulse generator, a matrix driver and an output bufier. Ten of the double triode phase shifting pulse generators are connected in cascade. When an input pulse is applied to the input of the cascaded generators, a series of spaced pulses is generated, one by each stage. The tenth stage generates the tenth pulse which may be used as a carry pulse. Each of the pulse generator stages is coupled to a matrix driver tube the outputs of which are fed into a pulse combining matrix. The matrix provides nine outputs each of which yields a predetermined number of pulses from 1 through 9. The matrix outputs are fed through nine output buffer tubes to output points which may be connected to external utilization means or to a complement generator which provides outputs consisting of pulses from 1 through 9 or complements of 9. Thus the system of the present invention as briefly described above provides at discrete output points any predetermined number of pulses from 1 through 9 and an additional carry or 10th pulse or complements of 9 under the operators control.

One object of the present invention is to provide a method of and means for electronically generating any predetermined numbers of pulses from 1 through 9 and an additional carry pulse.

Another object is to provide an electronic pulse generator for generating any predetermined number of pulses from one through 9 wherein time interval from one another.

' plate current flows and the voltage at cathode [2 Still another object is to provide a pulse generator for electronic computers and the lilze which requires fewer tubes and parts and is cheaper to make than such generators hitherto available.

A still further object is to provide a pulse generator for electronic computers and the like having greatly improved operating characteristics.

Another object is to provide a pulse generator having greatly improved reliability.

Still another object is to provide under selective control, either a predetermined number of pulses or pulses representing the complement of 9.

These and other objects will be apparent from the detailed description of the invention given in connection with the various figures of the drawing.

in the drawing:

Fig. 1 shows a circuit diagram of one form of ten cascaded phase shifting pulse generators.

Fig. 2 shows a circuit diagram of one form of the matrix drivers and the pulse combining matrix.

Fig. 3 shows a circuit diagram of one form of output buffers.

Fig. 4 shows a circuit diagram of one form of compliment generator.

Fig. 5 shows a diagrammatic representation of the time relationship of the pulses in the pulse generators of Fig. 1.

Fig. 6 shows a detailed circuit of one form of a phase shifting pulse generator stage.

Fig. 7 shows a block diagram of the various circuits of Figs. 1 through 4 combined to show their relationship one with the other.

Fig. 1 shows a circuit diagram of one form of cascaded phase shifting pulse generators in which a series of ten double triode tubes I l are connected in cascade. Each double triode includes two cathodes l2 and I6, heated by conventional means not shown, two corresponding grids l3 and H and two corresponding plates [4 and 18. Since the operation of each of these double triodes stages is the same it will be explained in connection with Fig. 6 which shows a single stage and in which corresponding numbers have been used to designate corresponding parts. An input pulse (Fig. 63) designated P(IN) is applied over input lead l5 to the first grid I 3. This pulse has an amplitude substantially greater than +Vi as indicated by the dotted line and this voltage +Vl is also the cathode bias applied to cathode 12(Kl through cathode resistor 22(Rl). While bias Vi is a bias suflicient to cut-off plate current to plate I 4(Pl), when the voltage on grid l2 exceeds this; bias, substantially saturation rises sharply. The second triode section including cathode 16(K2) grid I'HGZ) and plate 18(P2) is initially operated at saturation with cathode t grounded, plate l8 connected to a high voltage source, not shown, through resistor by means of lead is and grid I! also connected to the high voltage source-through resistor 2|. The rise in the voltage at cathode 12, described above, is difierentiated through capacitor 23 and applied to grid l1. However, since grid l1 draws current and represents a low impedance to positive pulses, the rise in voltage from cathode I2 is largely suppressed as shown by the curve marked P (IN) PERIOD. When the voltage of the pulse "at grid l3 returns to zero, the voltage at cathode 12 drops sharply and the differentiated negative pulse through capacitor 23 appears on grid ll.

This pulse, since it is in a negative direction,

sees a decreasing impedance at grid I! and. quickly cuts ofi the grid current. The resultingvoltage at grid H. is shown-as P.(OUT) PERIOD. This negative pulse ongrid I! quickly cuts oil current to plate is and results inasudden rise in voltage at. plate I8. As the-differentiated negative pulse on grid [7 returns-to" zero platecurrent is again establishedand the voltage at plate 18 returns uiclzlyzto its initial value. The net result of the above is a plate voltagepulseat plate; is as shown at 'P(OUT) whichis of the same form as the input pulse P(IN) but which is shifted in time by an amount equal to the-duration of this input pulse. Thus the double triode stage receives 'a pulse and .generatesa similar outputpulse of the same; form but delayed ;by a predetermined amount, :an-amount equalto the duration of the input pulse.

Returning to Fig. 1 it will be seen that there are ten of these ;..d0llb18 triode stages, designated as Sltthrough Slit, inwhich each'stage is. similar to the stage ofFigfi describedabove and each stage, except thelOth feeding the next succeeding stage. Each stage receives a pulse and generates a similar output pulse but displaced in time. Fig. 5 shows nine of these pulses where TI is the pulse generated by stages S! :of Fig.,1,'T2 is the pulse generated by stage .52, .etc. The output pulse'fromstage SI .iSJiBdUVBI' lead 25through difierentiatingcapacitor"26 to lead 21 where it appears differentiated as a sharp positive pulse representingthe leadingedge and a sharp negaitve pulse representing the trailingedge of the generatedpulse. :The outputs of the succeeding stages are similarlycoupled-to.leads 28 through at which leads-the .difierentiated form of pulses shown in 5 appear. Thedifierentiated form of pulse Ti appearsat leadfl, of pulse T2 at lead;28, and so on through T9 at lead :35. The tenth stage :Slll generates .a tenth pulse which may be .used as a carry pulse 'to another pulse generator or mayberutilizedin any desired-manner as, for instance, for resupplyingtthe .input pulse.

Fig. Zshows acircuit diagram of one form of pulse vcornbiningpma trix ,for receiving the differentiated pulses from the circuits of Fig. 1. The spaced 'pulseswhich are generated by the circuit of Fig. .1 areapplied :to. a pulse combining matrix made up :of resistors RI through R9 and the combined pulses appear across resistors RI through Rfiwhich are common to predetermined circuits of the matrix as will be set forth below. Vacuum tubes afi'through 44 may be inserted between the input leadsZJ through'35, corresponding to the similarly designated leads of Fig. l, and the matrix resistors to provide increased '4 sensitivity and decoupling. Each of these tubes may be a suitable vacuum tube as, for instance, a pentode 36 having cathode 46 heated by conventional means, not shown, a control grid 41 which receives a suitable bias through grid resistors 45 from a conventional source, not shown, screen grid 43 maintained at a-suitable positive voltage from a conventional source, not shown, suppressor grid 59 and plate 58. Plate 50 is connected over lead 69 to one end of one each of resistors-Rt through R9. The other end of resistor RI is connected through load resistor RI tocommon lead-.86 which supplies plate voltage from a conventional source, not shown. The

other end of each of resistors R2 through R9 is connected to leads 76 through respectively. The plate of tube 31 is connected over lead HI to-oneend of a second series of resistors R2 through R9 the other ends of which are connected to leads '58 throught5 respectively. In the same manner the plates of tubes 38' through 44 arexconnected overleads H through'll each to a series of resistors one less than the preceeding tube until tube id is connectedto asingleRQ resistor. Leads 78 throughsfifi are connected to load resistors R2. through Rwrespectively. Thus itwill' be seen that-Rl receives the output from only one tube, tube 35, through a single resistor R! and, hence, a single pulse appears across-RI each time the pulse generators of Fig. l are pulsed. Two pulses, one through each of the two R2 resistors, will appear across R2 each time the pulsegenerators are-pulsed. One pulse arrives through tube 36 and one through tube 31. In a similanmanner three pulses will appear across resistor R3 throughthe three R3 resistors and so on up to nine pulses which appear across resistor R9. Thus there is generate done through nine pulses "respectively across resistors R! through R9. Thesepulses are fed to further means through couplingcapacitors 5| through 58 and over'leads"tuthrough'vfifi respectively. It will be noted that :the diiierentiated pulse as shown inFig. 2 has positive and negative peaks. The bias appliedto thegridsof tubes 35 through 5% is sufiic-ientlynegative that only the positive peak affects the tube plate current-and hence is the only pulse to appear in the matrix from each tube.

Fig. 3 showsone form of output bulier circuit which maybe used to prevent interaction of further circuits in the systemfrom causing interaction between groups of pulses and which is also useful in eliminating cross products. The tubes in this bufler are supplied with a positive grid bias -so that only negative pulses of'more than a predetermined amplitude afiect the plate currents. This removes residual'undesired pulses produced by cross couplings in the matrix. The output bufier'includes triode sections 86 through 9 which may be portions of dual triodes as shown. These tubes may all be similar to tube 86 which includes cathode heated by conventional means, not shown, control grid 95 and plate 91. The inputto tube 86 is receivedfrom lead 6B, which is 'a continuation of lead 6U of Fig. 2. This input is applied to'grid 95 through current limiting resistor 98. Grid 96 is placed at a positive potential 'with respect to cathode 95'by means of a'conventional source of positive voltage, not shown, applied through resistor 99. Plate '9'! is energized from a conventional source of positive voltage, not shown, over lead [09 and through load resistor I 08. When a negative'pulse over lead "60 exceeds the positive grid bias, the

plate current is reduced causing the plate voltage to rise and thereby developing a positive voltage pulse across load resistor I00. The output pulse is applied to further means over lead IIO.

In a similar manner triode section 81 receives two pulses over lead GI and delivers two pulses acorss load IGI to output lead III; triode section 88 receives three pulses over lead 62 and delivers three pulses across load I02 to output lead II 2; triode section 89 receives four pulses over lead 03 and delivers four pulses across load I83 to out put lead II3; triode section 90 receives five pulses over lead 64 and delivers five pulses across load I04 to output lead II4; triode section 9! receives six pulses over lead 65 and delivers six pulses across load I05 to output lead H5; triode section 92 receives seven pulses over lead 68 and delivers seven pulses across load I06 to output lead IIS; triode section 93 receives eight pulses over lead 61 and delivers eight pulses across load I 81 to output lead III; and triode section 94 receives nine pulses over lead 68 and delivers nine pulses across load I88 to output lead II 8. The above thus describes circuits for generating from one to nine pulses as shown at AI to A9 inclusive. The combination shown in Figs. 1, 2' and 3 and described above may be utilized in many ways that will be apparent to those skilled in the art as a source of any number of spaced pulses from one through nine.

In electronic computers it is necessary to be able to select pulses representing any given numher or pulses representing the complement of the number. The complement generator shown in Fig, 4 if fed with one through nine pulses may be operated to yield zero, one, two, etc. through nine pulses, or nine, eight, etc. through zero, or the complements of the ascending series of numbers. Essentially the circuit consists in a series of nine double triodes, each of which receives an input of a given number of pulses and providing either of two outputs, one being the given number and the other furnishing the complement for another number. Selection by a switch control gives either the direct number output or the complement output. Output circuits are provided at which either the direct numbers or their complements are available.

Fig. 4 shows nine double tubes which may conveniently be double triodes H9, I20, I2I, I22, I23, I24, I25, I29 and I21 as shown. Input pulses over leads H8 through H8 are applied to the grids of these tubes each tube receiving a given number of pulses on both its grids. Since the cir cuits are symmetrical, the circuits of tube I I 9 will be described in detail. Tub-e II9 includes cathodes I30 and I3I heated by conventional means, not shown, grids I29 and I32 and plates I29 and I33. Grids I29 and I32 are coupled to the single pulse lead IIO by means of resistors I34 and I35 while a negative bias is supplied from a suitable source such as battery I31 through resistor I36. Cathode I30 is connected over leads I19 and I51 to the high end of resistor I10 the other end of which is grounded. When plate I28 is energized, the single pulse received over lead H is relayed to resistor I10. Plate I28 is energized in any suitable manner under control of the operator and switch I52. One way in which switch I52 may be utilized to energize plate I28 is shown in which switch I52, when closed, pulls down a plate of trigger connected double triode II placin a negative bias on grid I 48 of tube I46. Tube I46 may conveniently be a triode having plate I49, control grid I48 and cathode I41 heated by conventional means, not shown. When grid I48 goes negative, due to closing switch I52 and the presence of a bias from voltage source I54, the current to plate I49 through resistor I50 from source I 54 over lead I59 drops and plate I49 becomes more positive placing a positive bias on grid I42 of riode I39 through resistor I44. The triode I39 includes plate I43, grid I42 and cathode I4I heated by conventional means, not shown. Plate I43 is energized from voltage source I54 over lead I50. Cathode I4I returns to ground through resistor I40. When grid I 42 is made positive by closing switch I52, as described above, cathode I4I goes positive due to the cathode current drop placing a positive voltage on lead I38 and, hence on plate I28 and the corresponding plate of tubes I28 through I21. When plate i23 is energized in the above manner, cathode I38 repeats the pulses applied to grid I29 and provides an output over leads I79 and S51 across resistor I18. The pulses so placed on resistor 119 may be taken oh by sliding any one of switches I65, IE! o I68 to the corresponding contact point. In this way since one pulse is received over lead IIII, two pulses over lead III and so on, resistors I69 through I18 receive 0, 1 etc. through 9 pulses, resistor IE5 receiving six pulses, for example. These pulses may be selected in any desired manner by slide switches I66, IS? and I58. The desired sequence of pulses are placed on resistors I59 through I18 over leads I56 through I65 from tubes I I9 through I21 when one set of elements is energized over lead I 38 by closing switch 52. The sequence just described my be designated the direct sequence.

The complement sequence, that is, a sequence representing the complement of nine for each point on switches I69, I61 and I98 may be provided by closing switch I53. Closing switch I53 throws trigger tube I5I to the other side conducting and lead I 55 is energized in a manner corresponding to the way in which lead I33 is energized as described above. When lead I55 is energized, plate i528 and the correspnding plates in the other tubes are deenergized and plate I33 is energized together with the plates corresponding to it in tubes I23 through I21. When plate 33 is energized, cathode I3I is activated and the pulse from lead H0 on grid I32 is relayed over leads I88 and I 54 to resistor I11. It will be noted that this places a single pulse on resistor 51? and the corresponding points on switches I68, I81 and IE8 whereas in the direct sequence this resistor and these switch points carried eight pulses. Thus, the single pulse represents the complement of nine. In the same manner tubes I28 through I21 relay pulses representing complements of nine to resistors I69 through I13 and to the corresponding switch points. Thus, closing switch I52 provides a direct series of pulses zero through nine on the points of switches I56, it? and I68 while closing switch I53 provides a series representing the complements on these switch points.

Fig. '7 shows a block diagram-of a complete system made up of the components described above. The cascaded phase shifting pulse generators I83, shown in detail in Fig. 1, feed single spaced pulses over leads I84 to the matrix drivers I85, shown in detail in Fig. 2, which relay these pulses over leads I86 to the pulse combining matrix I81, also shown in detail in Fig. 2, which then provides a series of pulses from one to nine over leads I88 to the output bufiers I39, shown in detail in Fig. 3, which also relays a series of pulses from one through nine over leads I99 to the complement generator I 9I which under control of assume electronic switch 194 over directlead we or complement lea-d 433, as shown in detail in Figprovides either a direct series of pulses ifI'Oll'l zero through time are, complement series from nine through 'zerc over leads B5 to any suitable external :util'ization'means. The :manm in which this system is utilized in electronic computers in the "like will be apparent to those skilled in the :art.

While only .one embodiment oi the'rsresent invention has "been shown and described, many modifications of the present invention will 'be-a'pparent the spirit and scope of the invention :as set lorth in the sappendedeclaims will be :apparent-tothoseskilledsntheiamt.

What claimed is:

1. "In a pulse generating system, the zccmhinaticn of, :a plurality of single :pulse generators, time delay means for coupling said pulse generators in cascade to provide -a pluralit of substantially squallyspaced pu-lses, a resistive network matrix, and means tor ffeeding the last said pulse into esaldni'atriX for combining pulses to form predetermined groups of pulses.

2. Ina pulse generating system, the combination of, a piuraility-of puise responsivecsingle pulse generators, a pluralityo'f time delay coupling circuits for connecting said :pulse igen'erators in ca'soad-e to provide a series of substantially equally spaced pulses, a resistive network matrix, and means ior "feeding the last said pulses into said matrix for receiving said pulses and combining them to form predetermined groups of pulses.

3. ln apulse generating system, the combination "of, a plurality of similar electronic :pulse generating stages including time delay means inc'onpox atcd in each of said stages, coupling circuits tor connecting said stages in cascade-Ito pro-- vide a series of spacedupulses, resistivenetwork matrixiorreceiving said pulses, and a plurality of output :ci-rcults counted to said matrix for deriving fromsaid matrixidi'screte groups of pulses eachof said groups comprising :a predetermined number 'Of'iDlilSES.

l. a pulse generating system, the combination cf, :a plurality :of similar electronic pulse :gencrating stages including time delay circuits incorporated :in each of said stages, coupling circuits connecting said stages in cascade to provide a series of spaced pulses, an electrical :matrix for receiving said praises, a :plurality of :cutput circuits coupled to said matrix for deriving from said matrix discrete groups of :pulses each of said groups using a predetermined number .of pulses, and means for shifting said groups from one order of succession to a second order of succession.

:5. In a :piilee generator system, the combination'of, :a -pulse generator iorgenerating a series of individual pulsesan electrical matrix :for combining said :pu-lses :into :groups of pulses wherein each group comprises a predetermined number of pulses, a series of :discrete output circuits, and

8 switching means Ltor applying said pulses in said groups to said circuitsinoneio'f two predetermined sequences.

6. In a pulse generating system, thescombination of, a pulse generator 'forgenerating a series of individual pulses, an electrical network for combining said pulses into groups of pulses, out- :put circuits for receiving said groups :in pzredetermined sequence, and switch means for reversing-said sequence.

7 Ina pulse generating system, the combination "Ofy a pulse generator including a plurality of time delay circuits for generating a series of spaced pulses, an electrical network for combining said pulses into groups of pulses comprising numbers of pulses forming apredetermined sequence, a series of output circuits circuits :for applying said pulses in said sequence to said out- ;put circuits in a predetermined ordeniand switch means for altering said order.

:8. In a pulse generating system, the combinaticnof, a phase shifting pulse generatnr :for generating at least nine individual andspaoed pulses, at least :nine pulse receiving points, a pulse combining and distributing resistive network for receiwing saidipulses and for applying the first pulse to one of said receiving points,the first "and second of said pulses to a second of said receiving points and in like manner applying one more pulse to each succeeding receiving point'up to and including nine pulses to the ninth receiving point.

9. In a pulse generating system, the combination of, means for generating :groups of pulses comprising one ipulse through nine pulses, nine output terminals designated one through nine, nine electronic switches, circuits ior-applyingcne of said groups of pi-% to each of said switches, and 'COIJIBCtl'OIlS between each of said switches and two output terminals, oneof the last said terminals being the terminal designated corresponding to the number of :pulses in the group applied to the electronicswitch connected thereto and the other terminal losing the terminal designated with the complement of nine of the number of pulses .in the applied group for distributing pulses to said terminals in one sequence when said electronic switches are activated in one direc-tion andtor distributing pulses in a complement of :nine sequences when said electronic switches are activated in one direction and for distributing pulses in a complement of nine sequence when said electronic switches are activatedinaseconddirection.

NATHAN A.

References Cited in the'file of this patent UNITED PATENTS Number Name "Date 2,393,771 Compton Apr. 23, 1946 2,413,444 Rajchman June I4, 1949 2,515,395 Clark July 18,1951 2,572,891 Smith Oct. 30, 19 51 

